In recent years, light-emitting diodes (LEDs) have been widely used in various fields. Especially, blue LEDs made of gallium nitride can obtain white light in combination with yellow phosphor, of which not only the performance in brightness is higher than that of a conventional lamp or light bulb, but also the power consumption is lower than that of the conventional lamp or light bulb. In addition, the service life of the LED is longer than that of the conventional lamp or light bulb.
Presently, in manufacturing gallium nitride semiconductor light-emitting devices, due to the difference in the lattice constant between the gallium nitride semiconductor layer and a heterogeneous base material, dislocations easily occurs during the epitaxial growth of the gallium nitride semiconductor layer. Therefore, the luminous efficiency of the gallium nitride semiconductor light-emitting device is influenced.
Conventionally, a laser separation method is adopted to separate the gallium nitride semiconductor layer from the heterogeneous base material, or an etching method is adopted to remove a barrier structure between the gallium nitride semiconductor layer and the heterogeneous base material, so as to separate the gallium nitride semiconductor layer from the heterogeneous base material. In addition, the method of high-temperature etching method is adopted to remove an interface layer between the gallium nitride semiconductor layer and the heterogeneous base material, so as to separate the gallium nitride semiconductor layer from the heterogeneous base material. However, the methods mentioned above cannot solve the problem of poor luminous efficiency of the gallium nitride semiconductor light-emitting devices caused by dislocations during the epitaxial growth of the gallium nitride semiconductor layer.